all speculation but hard to imagine an oral surgeon would leave a root tip especially on an abscessed tooth which usually come out without breaking roots….that root may have been fractured and hard to pick up on X-ray. Either way it got taken out. The residual "pieces" could be fragment of bone surrounding tooth. It happens, its dentistry….move on with treatment with current practitioners bc they know more than you do

what I'm saying is you are not being neglected…the public should not make their own diagnosis. If you have a question you should address the practitioners not this board bc this is purely speculation from info given, no X-rays etc….technically this board is not utilized for that. Everything will be fine, the mouth is very resilient and you will heal fine and get a great result. Trust the professionals